The invention relates to a heat-developable light-sensitive element, particularly relates to a heat-developable light-sensitive element which gives a lowered fog and a high maximum density and is inhibited in the variation of density depending on the fluctuation of the developing condition.
Recently, it is strongly demanded to reduce the amount of the effluent of a processing liquid for protecting the environment and saving the space. Therefore, technology is required which relates to the heat-developable light-sensitive element suitable for the use of the medical diagnosis or the technological photography which is capable of being efficiently exposed by a laser imager or a laser image setter to form an image with a high resolution and a high sharpness. A simple heat development system using no liquid processing chemical and accompanying no environmental pollution can be provided by such the heat-developable light-sensitive element.
As the heat-developable light-sensitive element, a black-and-white heat-developable light-sensitive element so called xe2x80x9cdry silverxe2x80x9d has been known, which is described in various publications such as U.S. Pat. No. 5,343,043 and Research Disclosure (DS) No. 17,029.
Many photographic properties are required to the heat-developable light-sensitive element such as a lowered fog and a high maximum density. Many techniques are disclosed for improving the fog and the maximum density. However, a sufficient technical resolution has not be obtained by the known technology.
Japanese Patent Publication Open to Public Inspection (JP O.P.I.) No. 10-282601 discloses a method in which the radius of sphere of influence when the element is exposed to light of 30 xcexcJ/cm2 and developed at 120xc2x0 C. for 20 seconds is limited for the purpose of giving an image with a little tone variation. However, the publication does not describe with respect to the fogging property and the maximum density, even though the effect of the technique for giving an image without tone variation is recognized.
The object of the invention is to provide a heat-developable light-sensitive element having a low fogging and a high maximum density and an inhibited density variation depending on the fluctuation of the developing condition.
The invention and embodiments thereof are described.
A heat-developable light-sensitive element comprising a non-light-sensitive organic silver salt and a light-sensitive silver halide wherein an average radius r of the sphere of influence is from 0.35 xcexcm to 10 xcexcm when the element is exposed to light of from 35 xcexcJ/cm2 to 50 xcexcJ/cm2 and developed by a developing drum at a temperature of 123xc2x0xc2x13xc2x0 C. for a time of 16xc2x13 seconds.
It is preferable that the average radius of the sphere of influence r is from 0.50 xcexcm to 1.00 xcexcm in the heat-developable light-sensitive element described in the above.
The heat-developable light-sensitive element comprising a non-light-sensitive organic silver salt and light-sensitive silver halide and the ratio r2/r1 is from 1.5 to 3.0, wherein r1 is the average radius of sphere of influence when the element is exposed to light of from 35 xcexcJ/cm2 to 50 xcexcJ/cm2 and developed by a developing drum at a temperature of 123xc2x0xc2x13xc2x0 C. for a time of 8xc2x13 seconds, and r2 is the average radius of sphere of influence when the element is exposed to light of from 35 xcexcJ/cm2 to 50 xcexcJ/cm2 and developed by a developing drum at a temperature of 123xc2x0xc2x13xc2x0 C. for a time of 16xc2x13 seconds.
The ratio of the average radius of sphere of influence r2 to r1, r2/r1, is preferably within the range of from 2.0 to 2.8.
A preferable example of the developing drum is KONICA LASER IMAGER DRYPRO MODEL 722.